How to play the character information in dialogflow CX ? I want to play the uppercase/lowercase info

[Mohammad_Anas]

Hi all ,
I am to trying to read out the upper case / lower case information while reading  out the username to the end user .
I've tried :  <say-as interpret-as="characters" format="glyphs">Jö_4 2</say-as> 
but this glyphs attribute doesn't seem to work on df

please let me know if there is any other way to do it.
All the help is appreciated